<!doctype html> 
<html> 
<head> 
    <meta charset="utf-8"> 
    <title></title> 
    <style type="text/css">
#mes{
	width: 200px;height: 300px;border: 1px solid black;
}

    </style>
</head>
<body>



<div>121</div>
<div>321</div>
<script type="text/javascript">
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		a.innerHTML = 'assjdkal';
		document.body.insertBefore(a,document.body.children[1]);
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</script>
</body>
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